Hydrosilylation involving the use of platinum catalysts is a particularly important technique in the silicone industry, particularly in the production of organic modified silicones and silane coupling agents. Many attempts have been made in the past to improve the selectivity for the product structure or the hydrosilylation reaction rate in this process.
The following are examples of improvements in hydrosilylation reaction rates.
U.S. Pat. No. 5,359,111 describes a process where the hydrosilylation reaction is carried out in an oxygen gas atmosphere.
U.S. Pat. No. 5,449,802 describes a process where the hydrosilylation reaction is carried out in the presence of acetylene alcohol or a derivative thereof.
U.S. Pat. No. 5,481,016 describes a process where the hydrosilylation reaction is carried out in the presence of an alcohol having a tertiary structure or a derivative thereof.
U.S. Pat. No. 5,486,637 describes a process where the hydrosilylation reaction is carried out in the presence of alcohol having an unsaturated structure and a branched structure (tertiary or secondary) or a derivative thereof.
Chem. Eur. J. 1998, 4. No. 10, p. 2008-2017 describes a process where the hydrosilylation reaction is carried out in the presence of a naphthyl ketone.
Japanese Unexamined Patent Application (Kokai) 11-80167 describes a process where the hydrosilylation reaction is carried out in the presence of a sulfur compound.
Methods for bringing about a hydrosilylation reaction in the presence of a platinum catalyst and various additives have been proposed in order to improve the selectivity for certain products during hydrosilylation. The following are examples of reactions for the hydrosilylation of allyl chlorides with hydrochlorosilanes in the presence of a platinum catalyst. Japanese Unexamined Patent Application (Kokai) 9-157276 and Japanese Unexamined Patent Application (Kokai) 55-145693: phosphines are used as additives. Japanese Unexamined Patent Application (Kokai) 9-192494: tertiary amines with alkyl or aralkyl groups as substituents are used as additives. Japanese Unexamined Patent Application (Kokai) 10-72474: amino alcohol derivatives are used as additives.
U.S. Pat. No. 5,563,287 and U.S. Pat. No. 5,567,848 disclose methods featuring the use of cycloalkadiene compounds in the hydrosilylation of alkyne-based hydrocarbons.
Although the prior art discloses methods for improving the yield of the target product in specific systems, no method widely applicable to hydrosilylation reactions has yet been established for satisfactorily increasing the proportion of the target product over the proportion of by-products.
An object of the present invention is to allow target products (.beta.-hydrosilylated products) having a structure in which silicon atoms are bonded to the terminal carbon atoms of unsaturated groups, which are the reactive groups of unsaturated compounds, to be produced more efficiently than in the past compared to by-products (substituted reaction products produced in the case of allyl chlorides and the like, or .alpha.-hydrosilylated products produced in the case of styrenes and the like) during hydrosilylation reactions in which the aforementioned unsaturated compounds having terminal unsaturated groups and silicon compounds having hydrogen atoms directly bonded to silicon atoms are allowed to react in the presence of a platinum catalyst.